A solid waste mixture contains potassium nitrate and silica dust. Pure potassium nitrate can be reclaimed from this mixture using the method described below.

Use words from the box to complete the sentences. You may use each word once, more than once, or not at all.

\begin{array}{|cccccc|} \hline \text{crystallise} & \text{dissolve} & \text{filter} & \text{filtrate} & \text{residue} & \text{solvent} \\ \hline \end{array}

Add the solid mixture to a beaker of boiling water, which acts as the hot ___________________ (1).
Stir the mixture thoroughly to ensure all the potassium nitrate will ___________________ (2) completely.
Pass the hot suspension through filter paper. The insoluble silica remains on the paper as the ___________________ (3).
Allow the hot filtrate to cool slowly in an ice bath so that the potassium nitrate can ___________________ (4) out of the solution.
Finally, ___________________ (5) the cold mixture to separate the purified potassium nitrate solid from the supernatant liquid.

A solid waste mixture contains potassium nitrate and silica dust. Pure potassium nitrate can be reclaimed from this mixture using the method described below.

Use words from the box to complete the sentences. You may use each word once, more than once, or not at all.

\begin{array}{|cccccc|} \hline \text{crystallise} & \text{dissolve} & \text{filter} & \text{filtrate} & \text{residue} & \text{solvent} \\ \hline \end{array}

Add the solid mixture to a beaker of boiling water, which acts as the hot ___________________ (1).
Stir the mixture thoroughly to ensure all the potassium nitrate will ___________________ (2) completely.
Pass the hot suspension through filter paper. The insoluble silica remains on the paper as the ___________________ (3).
Allow the hot filtrate to cool slowly in an ice bath so that the potassium nitrate can ___________________ (4) out of the solution.
Finally, ___________________ (5) the cold mixture to separate the purified potassium nitrate solid from the supernatant liquid.

Elements, compounds and mixtures

Question 18

Markscheme

Elements, compounds and mixtures

Question 18

Markscheme

Elements, compounds and mixtures

Question 18

Elements, compounds and mixtures Questions

Elements, compounds and mixtures

Question 18

Elements, compounds and mixtures Questions